curl http://127.0.0.1:8181/v1/metrics/ panics (only with trailing /)

[tiffanyfay]

/tasks/ and /plugins/ redirect to /tasks and /plugins, but curl http://127.0.0.1:8181/v1/metrics/ panics with:

PANIC: runtime error: index out of range
goroutine 87 [running]:
github.com/codegangsta/negroni.(*Recovery).ServeHTTP.func1(0xf09d80, 0xc820145e40, 0xc820f86780)
    /Users/tjerniga/.gvm/pkgsets/system/global/src/github.com/codegangsta/negroni/recovery.go:34 +0xe9
github.com/intelsdi-x/pulse/mgmt/rest.parseNamespace(0xc82011846f, 0x1, 0x0, 0x0, 0x0)
    /Users/tjerniga/.gvm/pkgsets/system/global/src/github.com/intelsdi-x/pulse/mgmt/rest/server.go:272 +0x113
github.com/intelsdi-x/pulse/mgmt/rest.(*Server).getMetricsFromTree(0xc820124a80, 0xf09d80, 0xc820145e40, 0xc8200b21c0, 0xc820118580, 0x1, 0x1)
    /Users/tjerniga/.gvm/pkgsets/system/global/src/github.com/intelsdi-x/pulse/mgmt/rest/metric.go:44 +0x8a
github.com/intelsdi-x/pulse/mgmt/rest.(*Server).(github.com/intelsdi-x/pulse/mgmt/rest.getMetricsFromTree)-fm(0xf09d80, 0xc820145e40, 0xc8200b21c0, 0xc820118580, 0x1, 0x1)
    /Users/tjerniga/.gvm/pkgsets/system/global/src/github.com/intelsdi-x/pulse/mgmt/rest/server.go:210 +0x5c
github.com/julienschmidt/httprouter.(*Router).ServeHTTP(0xc820113bc0, 0xf09d80, 0xc820145e40, 0xc8200b21c0)
    /Users/tjerniga/.gvm/pkgsets/system/global/src/github.com/julienschmidt/httprouter/router.go:299 +0x193
github.com/codegangsta/negroni.Wrap.func1(0xf09d80, 0xc820145e40, 0xc8200b21c0, 0xc820118560)
    /Users/tjerniga/.gvm/pkgsets/system/global/src/github.com/codegangsta/negroni/negroni.go:41 +0x50
github.com/codegangsta/negroni.HandlerFunc.ServeHTTP(0xc820f86820, 0xf09d80, 0xc820145e40, 0xc8200b21c0, 0xc820118560)
    /Users/tjerniga/.gvm/pkgsets/system/global/src/github.com/codegangsta/negroni/negroni.go:24 +0x44
github.com/codegangsta/negroni.middleware.ServeHTTP(0xf09a48, 0xc820f86820, 0xc820f868a0, 0xf09d80, 0xc820145e40, 0xc8200b21c0)
    /Users/tjerniga/.gvm/pkgsets/system/global/src/github.com/codegangsta/negroni/negroni.go:33 +0xaa
github.com/codegangsta/negroni.(middleware).ServeHTTP-fm(0xf09d80, 0xc820145e40, 0xc8200b21c0)
    /Users/tjerniga/.gvm/pkgsets/system/global/src/github.com/codegangsta/negroni/negroni.go:33 +0x53
github.com/codegangsta/negroni.(*Recovery).ServeHTTP(0xc820f86780, 0xf09d80, 0xc820145e40, 0xc8200b21c0, 0xc820118520)
    /Users/tjerniga/.gvm/pkgsets/system/global/src/github.com/codegangsta/negroni/recovery.go:45 +0x75
github.com/codegangsta/negroni.middleware.ServeHTTP(0xf09a20, 0xc820f86780, 0xc820f86860, 0xf09d80, 0xc820145e40, 0xc8200b21c0)
    /Users/tjerniga/.gvm/pkgsets/system/global/src/github.com/codegangsta/negroni/negroni.go:33 +0xaa
github.com/codegangsta/negroni.(middleware).ServeHTTP-fm(0xf09d80, 0xc820145e40, 0xc8200b21c0)
    /Users/tjerniga/.gvm/pkgsets/system/global/src/github.com/codegangsta/negroni/negroni.go:33 +0x53
github.com/intelsdi-x/pulse/mgmt/rest.(*Logger).ServeHTTP(0xc820114120, 0xf09d80, 0xc820145e40, 0xc8200b21c0, 0xc8201184c0)
    /Users/tjerniga/.gvm/pkgsets/system/global/src/github.com/intelsdi-x/pulse/mgmt/rest/log_handler.go:46 +0x387
github.com/codegangsta/negroni.middleware.ServeHTTP(0xf099f8, 0xc820114120, 0xc820f86840, 0xf09d80, 0xc820145e40, 0xc8200b21c0)
    /Users/tjerniga/.gvm/pkgsets/system/global/src/github.com/codegangsta/negroni/negroni.go:33 +0xaa
github.com/codegangsta/negroni.(*Negroni).ServeHTTP(0xc820113b30, 0xf09ce8, 0xc8200984d0, 0xc8200b21c0)
    /Users/tjerniga/.gvm/pkgsets/system/global/src/github.com/codegangsta/negroni/negroni.go:73 +0x122
net/http.serverHandler.ServeHTTP(0xc820124b40, 0xf09ce8, 0xc8200984d0, 0xc8200b21c0)
    /Users/tjerniga/.gvm/gos/go1.5/src/net/http/server.go:1862 +0x19e
net/http.(*conn).serve(0xc820099130)
    /Users/tjerniga/.gvm/gos/go1.5/src/net/http/server.go:1361 +0xbee
created by net/http.(*Server).Serve
    /Users/tjerniga/.gvm/gos/go1.5/src/net/http/server.go:1910 +0x3f6

In server.go it makes ns len 0 and then tries accessing ns[0]

func parseNamespace(ns string) []string {
    if strings.Index(ns, "/") == 0 {
        ns = ns[1:]
    }
    ns[len(ns)-1] == '/' {
        ns = ns[:len(ns)-1]
    }
    return strings.Split(ns, "/")
}

Should be

if len(ns) > 0 && ns[len(ns)-1] == '/' 

instead

Not sure what about : instead of * makes the GET redirect (though it would break the rest of namespace)
e.g.

curl http://127.0.0.1:8181/v1/plugins/
<a href="/v1/plugins">Moved Permanently</a>.

Going to http://127.0.0.1:8181/v1/metrics/ seems fine and redirects to /metrics, but http://localhost:8181/v1/metrics/ mimics the curl with a panic.